It appeared to be triangular in shape with 4 lights - a bright white one at the front, to dimmer white ones on the back corners and a red one in the middle. It was raining and cloudy, so the craft was reasonably low (less than 1000 feet I would guess). It moved relatively slow (compared to a commercial jet). It made no sound. I was biking to work and noticed it in the sky. I stopped to watch it, and heard nothing (even after it had disappeared from sight behind buildings). Plus, there were no commercial aircraft permitted to fly yesterday morning, because of the terrorist attacks in the US. The two things that seemed strange to me, was the fact that there was no sound (and it wasn't as if there was a lot of traffic on the roads to drown it out), and the pattern of the lights.